• Betting points to red wave
• Senate control revolves around five close races
• Positions ahead of markets going in-play

This is a huge day in US politics, with voting underway for the Senate and House of Representatives. At stake, control of Congress at a pivotal moment in US and world history. It has profound implications for Joe Biden's presidency and re-election chances in 2024.

Naturally, it is also a huge night for betting on politics. Betfair's markets will go live once polls close, and betting will be available for both state and nationwide markets, as the results for each county are being declared.

At 7am Eastern Time, these were the chances of victory implied by Betfair's live odds:

House of Representatives

HOUSE MAJORITY: 93% REPUBLICAN
DEMS OVER/UNDER 200: 56% UNDER

Senate

OVERALL CONTROL: 67% GOP
RESULT BY STATE: REPUBLICAN 52, DEMOCRAT 48 (46 as per market rules excluding Independents)

ARIZONA: 57% DEMOCRAT
PENNSYLVANIA: 58% REPUBLICAN
GEORGIA: 62% REPUBLICAN
NEVADA: 68% REPUBLICAN
NEW HAMPSHIRE: 68% DEMOCRAT
WISCONSIN: 89% REPUBLICAN
OHIO: 90% REPUBLICAN

GOVERNORS

WISCONSIN: 67% REPUBLICAN
NEVADA: 81% REPUBLICAN
ARIZONA: 83% REPUBLICAN
GEORGIA: 91% REPUBLICAN
KANSAS: 54% DEMOCRAT
OREGON: 61% DEMOCRAT
MICHIGAN: 82% DEMOCRAT
NEW MEXICO: 84% DEMOCRAT
MINNESOTA: 90% DEMOCRAT
PENNSYVLANIA: 92% DEMOCRAT

So, the betting signals are clear enough but plenty of uncertainty remains. The Republicans will win the House, but control of the Senate remains very much in-play. Here's my take.

(1/?) My predictions bets and for the #Midterms2022 (to be updated in-running).

Senate: Republican 51-49 Democrats (Georgia run-off to decide).

House: Republican 231-Democrat 204 https://t.co/ZsoCEv8Kiw

-- Political Gambler (@paulmotty) November 7, 2022

As a broad analysis, I simply can't see how this is a good night for the Democrats. They are 4-5% down on the generic ballot on their position when winning the House 222-213.

As incumbents of the White House, all recent history points to a negative reaction, especially with inflation high and Biden's approval ratings languishing around 42%. They trail Republicans on the key policy indicators - crime and economy. It should all point to a red wave.

Senate very much still in-play

However, we saw in 2018 that the narrative that emerges from the House is not necessarily reflected by the Senate results. Remember, only 35 of the 50 states have Senate races, compared to all 435 House districts.

Last time, with Donald Trump as President, the Democrats scored a 'blue wave', gaining 42 seats in a 235-199 victory. Yet they went backwards in the Senate, because the key states in-play showed a different trend.

Again, if polling is to be believed, the Senate remains firmly in Democrat sights and could very much save the night for Biden. I expect the night to be dominated by five, close Senate races - Arizona, Georgia, Pennsylvania, Nevada, New Hampshire.

Once polls close and the betting goes live in-running, it is easy to imagine favouritism flipping at least once in any of those five. My prediction is Republicans to win Nevada and Georgia, with the latter needing a run-off, and the other three going Democrat. That would produce a 51-49 win for the GOP.

However none of these specific states are based on strong opinions. The only one about which I am still carrying a live bet is Fetterman to win Pennsylvania for the Dems. In this situation, it makes better sense to focus where I do have confident views - the Senate Majority and Total Republican States.

Big state betting upsets are rare

The core idea behind the strategy is to dismiss all the big outsiders in the state betting. The forecasts, whether from prediction models or betting signals, are higher than 75% for one party. History shows these states very, very rarely lose. The US electorate isn't that unpredictable.

Even in the least predictable election in 2016, Trump's upsets in states were at most 5.04/1. The shortest priced-upset beyond the five aforementioned states is 8.07/1.

If that is correct, the Republicans will win between 49 and 54 seats. Six outcomes, with a couple of outliers at the ends. I think the middle - 50, 51 and 52 - represents tremendous value at combined odds around even money.

It covers so many different outcomes among those five states. When the live betting starts, I expect these middle-ranges to trade much shorter than now and be easily coverable later in the event.

Regarding the Senate Majority market, I covered this in the latest entry to Politics Live. In short, read the rules.

A Democrat majority requires they win 51 seats, plus the two Independents who caucus with them (Sanders and King). So, in total, they would need 53. That option is way too short at 12.011/1.

Will Democrats win 200 seats?

Regarding the House, GOP leader Kevin McCarthy was asked what he defined as a 'red wave'. He said anything over 20, (which would equate to 233-202). Fair call. I'd say Democrats getting less than 200 is the line - a good heat in our Total Democrat Seats market. My prediction is 231-204.

These, I believe, will be the three exciting markets on Wednesday morning - Senate Majority, Republican Senate Seats and Democrat House Seats.

Results won't start arriving until after midnight and from the West coast, after 3am UK time. If you can, it makes good sense to have a sleep to prepare for what is certainly an all-nighter.

Where to watch

CNN (Sky Channel 506, Freeview 207)
Wide variety of US networks live on Twitter, online.
Fivethirtyeight.com for live results and polling model projection

Follow Paul on Twitter and check out his website, Political Gambler.

Bet here:

Senate Majority

Total Democrat Senate Seats

House of Representatives Majority

Total Democrat House Seats

Total Republican Senate Seats