Those views from voters have come as former President Donald Trump looked poised to rack up wins over longshot GOP candidate Nikki Haley in the 15 states holding Republican primaries on Tuesday. He’s aiming to further cement his status as his party’s pick to take on President Joe Biden in November’s general election.

Related: Trump leads Biden in 7 swing states and is favored on handling the economy: poll

Tuesday’s exit polls also found abortion ranked as the third-most important issue for GOP voters in North Carolina, with 11% support, while foreign policy got 9% support.

For Republican primary voters in Virginia, abortion and foreign policy were tied in terms of their importance, with both getting 11% support.

Tuesday’s exit polls had some similarities with surveys for South Carolina’s GOP primary on Feb. 24. Exit polls in that state last month found 36% of Republican voters said immigration is the most important issue, 33% said the economy, 13% said foreign policy and 10% picked abortion. In addition, 82% viewed the state of the U.S. economy as either “not so good” or “poor.”

The increased importance of immigration appears to be helping Trump solidify his hold on GOP voters. His calls for building a wall along the U.S. border with Mexico were a signature feature of his successful 2016 presidential campaign.

Immigration also ranked as the most important issue facing the country in a Gallup poll of all voters released last week.

The surveys come after a bipartisan Senate deal on border measures collapsed last month, hit by Trump’s opposition to it.

Now read: Trump’s historic deportation plan would hit these industries the hardest