Robert Sarvis, the Libertarian candidate for Virginia governor last fall whose surprising support was seen as a sign of discontent with both major-party candidates, has qualified for the ballot for the U.S. Senate.

Sarvis will appear on the ballot with Sen. Mark R. Warner (D-Va.), the first-term incumbent, and Ed Gillespie, the former chairman of the Republican National Committee.

With 19,000 valid signatures on his nominating petitions, the Libertarian far exceeded the minimum of 10,000 needed from registered voters in the state to get on the ballot, according to his campaign.

Less clear is whether Warner, the most popular politician in the state, or Gillespie, still largely unknown among Virginia voters, will prompt the same desire among voters for a third choice that characterized last year’s matchup between Terry McAuliffe (D) and Ken Cuccinelli II (R).

Bob Holsworth, a Richmond-based political scientist, said that Warner and Gillespie should be concerned about Sarvis’s entry into the race. But Holsworth said he expected the two to focus more on “issue distinctions” and less on the “incredibly personal and negative” attacks that characterized the McAuliffe-Cuccinelli race and that voters found so distasteful.

“To the extent that he has an impact, Sarvis’s candidacy may be a bit more worrisome to Gillespie inasmuch as he received 10 percent of the vote in Republican-leaning Chesterfield County in 2013,” Holsworth said. “At the same time, Sarvis does draw young, libertarian-oriented voters as well, and he could take votes from Warner, especially on college campuses and among young professionals.”

Although Libertarians have a record of not making big waves in Virginia politics, Sarvis attracted nearly 7 percent of the vote in November in a race that McAuliffe won with a margin of less than three percentage points.

It’s not clear, however, that Sarvis — a 37-year-old software developer and lawyer with master’s degrees in math and economics — was a spoiler for McAuliffe or Cuccinelli. He performed well in a number of heavily Republican counties scattered across the state, but he also outperformed his statewide number in the Democratic enclaves of Roanoke and Charlottesville — and in the purple suburbs of Richmond.

A Washington Post/Abt-SRBI poll published the week before last fall’s election showed Sarvis winning 8 percent of the vote, but when asked whom they would support if Sarvis were not in the race, those voters split roughly evenly between McAuliffe and Cuccinelli, 53 percent vs. 42 percent.

Why has Sarvis returned to the campaign trail? Because “all of the themes from my campaign last year are still relevant, even more so with respect to the federal government’s overreach and failings,” he wrote in a statement to the media.

Sarvis also called out directly to Gillespie and Warner with a demand to be included in debates. Sarvis was shut out of debates last fall in part because of his low performance in public polls.

“It’s the right thing to do for Virginia voters. I am willing to debate either or both of them at any time, at any location, under any conditions,” Sarvis wrote.