ROCKVILLE, Md. (AP) — President Joe Biden and former President Donald Trump look to add to their string of victories and pad their delegate totals in Maryland on Tuesday as the presidential primary campaign enters its final weeks. Voters will also decide contested primaries in a U.S. Senate race that has further complicated Democratic efforts to keep control of the narrowly divided chamber this fall.

Maryland’s presidential primaries won’t have much of an impact on the races for the Democratic and Republican nominations, as both Biden and Trump have already been crowned as their parties’ presumptive nominees. But the Maryland ballots feature options that have proved to be stubborn irritations to both campaigns in recent contests – for Biden, it’s “ uncommitted ” and for Trump, it’s former United Nations Ambassador Nikki Haley.

In the Pennsylvania primary in April, for instance, the Democratic primary saw a surge in write-in votes after activists urged voters to write “uncommitted” on the ballot in lieu of voting for Biden. In the Republican contest, Haley received about 17% of the vote, despite having dropped out of the race in early March. Haley got almost 22% of the vote in Indiana’s presidential primary on May 7.