WASHINGTON — President Donald Trump has repeatedly encouraged voters to pretend he's on the ballot this Election Day. He's not, of course. But there is reason to believe that Tuesday's midterms, above all, will be a referendum on his performance over the last two years. History, polling and early voting numbers suggest it could be a difficult night for Trump's Republican Party, though the political map, not to mention a fresh round of gerrymandering, could limit Democratic gains. Voters are in the mood for change, according to the AP Voter Poll, which found that roughly three-quarters of voters say they feel “angry” or “dissatisfied” with the way things are going in the country today. Most appear to blame the Trump administration for high costs. About 6 in 10 say higher than usual prices are “more because of Trump’s policies” rather than “more because of factors outside Trump’s control.” Additionally, about 70 percent of voters want Congress to provide more checks and balances on the presidency. Democrats are looking to win majorities in the House and Senate, which