(CNN) Senate Majority Leader Mitch McConnell, who has long resisted Democratic calls to pass additional election security legislation, threw his support Thursday behind an amendment to provide $250 million in grants to states to bolster election security.

The move came on the same day Democrats planned to offer their own amendment in the Appropriations Committee to give $500 million to states to improve their election security infrastructure.

A spokesman for McConnell explained that the leader never opposed additional funds for the states but was waiting for the formal appropriations process, which is underway now, to seek it.

Until his floor speech, which took place about a half hour before the committee was set to meet, McConnell had not publicly called for the $250 million in additional election security funding.

By backing the additional funds, McConnell may neutralize a key political attack by Democrats against Republicans heading into the 2020 campaigns.

Democrats have aggressively pushed for more money, in the wake of Russian interference in the 2016 election and concerns that other nations, such as Iran, North Korea, and China, will try to interfere in the 2020 election.

A Democratic aide said McConnell had "relented" to Democratic pressure and Senate Majority Leader Chuck Schumer said it was a "victory" for Democrats, even though it wasn't as much money as they wanted and didn't include other election reforms backed by Democrats.

"After months and months and months of Republican resistance and months of insistent Democratic pressure, Senate Republicans have finally agreed to support our Democratic requests for additional election security funding in advance of the 2020 elections," Schumer said.

Speaking on the Senate floor, McConnell said he was "proud" to co-sponsor the amendment with committee chairman Richard Shelby, a Republican from Alabama, and Sen. Patrick Leahy, a Democrat from Vermont, the committee's vice chairman.

The panel approved the funding on a bipartisan voice vote a short time later. It still must be approved by the full Senate as well as the Democratic-controlled House before going to President Donald Trump for his possible signature.

In recent months, McConnell has turned back multiple efforts by Democrats to pass more election security funding and other reforms they believe are needed, such as requiring federal campaigns to report any contacts with foreigners. He has cited successful efforts by the Trump administration with the financial backing of Congress to strengthen state and local elections systems and ward off cyber-attacks.

He has argued the foreign interference problems like the nation faced in 2016 did not resurface in 2018, a sign their efforts to improve election security were successful.

McConnell has also warned that Democrats want to centralize election control in Washington, not in the states like it is now and complained that their efforts to pass major elections reforms on the Senate floor via unanimous consent requests were nothing more than political stunts.

The Kentucky Republican said the new funding would boost Washington's spending on election security to over $600 million and will ensure the states have the authority to direct the spending and not have the federal government dictate how they use it.

"That will bring our total allocation for election security to more than $600 million since fiscal 2018," McConnell said. "It's a crucial issue. The Trump administration has made enormous strides to help states secure their elections without giving Washington new power to push the states around. That's how we continue the progress we saw in 2018 and that's exactly what we're doing"

Two Republicans on the committee expressed concerns about approving more funds for the states because they still haven't used all the $380 million they already got.

GOP Sen. James Lankford of Oklahoma said the states have only spent $128 million of that pot and still have $252 million unspent.

"I am not going to oppose this but I'm going to ask the we do really good oversight. We're just handing states money and they're glad to take it but we are not even requiring they spend it much less show us how they are spending it before we hand them more money," said Lankford, who has worked for years on election security legislation.

On Wednesday, Sen. Shelley Moore Capito, a Republican from West Virginia, also seemed wary of approving more funds, in part because past efforts to boost election security were successful.

"I think we need to look at the considerations of the secretaries of state and the intelligence community as to whether they feel our elections in 2020 will be safe. We had a private, classified briefing where I came away the with assurances that our elections are safe in 2020," she said. "A lot of the money of the $380 million we appropriated last year, hasn't even put out the door yet."