Few Iowa politics watchers doubt that Democrats will gain ground in the state House today–the only question is how much will the Republican majority shrink.

In contrast, the Iowa Senate landscape could shift in either direction. Republicans now hold 29 seats and are unopposed in Senate district 1, where independent Senator David Johnson is retiring. They are also outspending several Democratic incumbents in districts Donald Trump carried in the last presidential election. Democrats currently hold 20 Senate seats, but they could add to their ranks today, despite a difficult map and a couple of bad breaks over the summer.

Here’s how the key races look going into election day, based on voter registration totals, recent voting history, absentee ballot numbers, and where Democratic or Republican leaders have made large expenditures.

As was the case two years ago, Democratic candidates are at a financial disadvantage in almost all of the Iowa Senate districts both parties are targeting.

The disparity adds another challenge to a party already facing a difficult path to gaining ground in the upper chamber. Republicans currently hold 29 of the 50 Senate seats and are guaranteed to pick up the district independent Senator David Johnson is vacating.

Five weeks before the general election, the Republican Party of Iowa has begun airing television commercials to promote Senate Majority Leader Jack Whitver and State Senator Julian Garrett.

The advertising suggests that Republican internal polling shows Democrats Amber Gustafson and Vicky Brenner within striking distance in Senate districts 19 and 13, respectively. Democratic internal polling presumably shows competitive races too, since former President Barack Obama included Gustafson and Brenner on his list of Iowa endorsements this week. Only five state legislative candidates made the cut.

Republicans are all but guaranteed to maintain control of the Iowa Senate after November and could expand their majority, now at 29 out of 50 seats. However, Democrats have a chance to pick up a few districts as they work toward winning back the chamber in 2020.

A record number of women running for office in Iowa this year has translated into a record number of women who will appear on our state’s general election ballot. Iowa State University’s Carrie Chapman Catt Center for Women and Politics noted that 85 women (86 percent of female candidates on Iowa’s primary ballot) won their party’s nominations yesterday.

More women than ever will likely win Iowa House seats this November (current number: 28 out of 100). Female representation will almost certainly increase in the state Senate too and could exceed the previous record (ten out of 50 senators in 2013-2014). Follow me after the jump for details.

More Iowa women are running for office in 2018 than ever before, which could lead to record numbers of female state representatives and senators next year.

However, in other meaningful ways, Iowa’s legislature could become less diverse after the November election.