With the general election matchup against President Obama beginning to take shape, Mitt Romney won the Republican primaries in Maryland and Washington, D.C. on Tuesday.

NBC News projected Romney would win the D.C. and Maryland primaries – the latter of which by a significant margin over his main rival, Rick Santorum.

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Republican presidential candidate Mitt Romney attends a town hall style meeting April 2 in Milwaukee, Wis.

The former Massachusetts governor had looked to move closer to putting the drawn-out Republican primary behind him, and beginning a new chapter – the general election campaign versus Obama.

Polls were set to close at 9 p.m. ET in Wisconsin, the top prize in Tuesday’s slate of contests. Romney had battled fiercely in the state against Santorum, who needed a win there to keep his hopes alive heading into the next group of contests on April 23, which includes his native Pennsylvania.

Romney has accrued 490 total delegates through March 24, according to NBC News’ count. Santorum had won 203, while former House Speaker Newt Gingrich was at 137 and Texas Rep. Ron Paul had won 34. A total of 92 delegates are at stake in Tuesday’s three contests, with 1,144 needed to secure the Republican nomination.