Two presidents, two closing arguments
President Donald Trump and former President Barack Obama spent the last week of the campaign in the same battlegrounds, offering voters opposite accounts of the economy. Trump held two rallies in Texas on Tuesday, in Lubbock and Corpus Christi, his fourth trip to the state since Labor Day, campaigning for Republican Senate candidate Ken Paxton. Obama headlined events for Democratic candidates in the states where the Senate map is tightest.
About 210 million registered voters will decide control of the full House and a third of the Senate on November 3. Early and mail voting is already under way in most states, and the Postal Service has urged voters to post ballots this week.
Cost of living dominates the closing message
Polling averages have put Trump's approval rating in the high 30s, with one national tracking survey near 32 percent. Voters name the cost of living, fuel prices and the economic fallout of the war with Iran as their main concerns. Those numbers have widened the field of competitive House races, and strategists in both camps now expect Democratic gains larger than forecast earlier in the cycle.
Republicans are defending a narrow Senate majority. The closest contests are in Michigan, Texas and Alaska, where turnout and late-deciding independents will settle the result. Democrats need a net gain of a handful of seats. Republicans need to hold seats in states where the president's approval sits below his national figure.
Legal fights shadow election day
The Justice Department has sued Alaska election officials, seeking to block certification of the Senate result if Republican Senator Dan Sullivan loses. A federal judge separately ruled that the department unlawfully fired Maurene Comey, a prosecutor whose dismissal became a campaign theme. Both cases are being cited by each party as evidence of what is at stake.
Republicans also face fresh uncertainty in two Senate races that tightened in the final days, while a Democratic House candidate in Alaska delayed campaign events after what her campaign described as minor injuries in a car crash.
Results will begin arriving after the first polls close at 6pm Eastern on November 3. Officials in several states warn that close races could take a week or more to call as mail, provisional and military ballots are counted.