© Greg Nash
Sen. Rand Paul
Randal (Rand) Howard PaulBooker, Harris have missed most Senate votes Trump vetoes measure ending US support for Saudi-led war in Yemen Bottom line MORE (R-Ky.) predicted on Sunday that the Supreme Court will likely strike down President Trump
Donald John TrumpGrassroots America shows the people support Donald Trump Trump speaks to rebel Libyan general attacking Tripoli Dem lawmaker: Mueller report shows 'substantial body of evidence' on obstruction MORE's emergency declaration, adding that the president's actions went against "the will of Congress."
Randal (Rand) Howard PaulBooker, Harris have missed most Senate votes Trump vetoes measure ending US support for Saudi-led war in Yemen Bottom line MORE (R-Ky.) predicted on Sunday that the Supreme Court will likely strike down President TrumpDonald John TrumpGrassroots America shows the people support Donald Trump Trump speaks to rebel Libyan general attacking Tripoli Dem lawmaker: Mueller report shows 'substantial body of evidence' on obstruction MORE's emergency declaration, adding that the president's actions went against "the will of Congress." 
Brett Michael KavanaughGrassroots America shows the people support Donald Trump The Hill's Morning Report — Category 5 Mueller storm to hit today On The Money: Cain 'very committed' to Fed bid despite opposition | Pelosi warns no US-UK trade deal if Brexit harms Irish peace | Ivanka Trump says she turned down World Bank job MORE and Neil Gorsuch, Trump's Supreme Court nominees, "may rebuke him on this."ADVERTISEMENT
Trump's emergency declaration is already facing legal challenges. Trump predicted last month that the 9th U.S. Circuit Court of Appeals will block his move to declare a national emergency to build the U.S.-Mexico border wall — but that he'll win the fight at the Supreme Court.
He said at the time that he hoped the administration would "get a fair shake and we'll win in the Supreme Court, just like the [travel] ban." He added that Republicans who were supporting Trump's emergency declaration after criticizing Obama's actions "will and should be condemned for hypocrisy."
Trump declared a national emergency after Congress passed legislation giving him $1.375 billion for physical barriers along the border, less than the $5.7 billion he requested. "Congress clearly expressed its will not to spend more than $1.3 billion and to restrict how much of that money could go to barriers. Therefore, President Trump’s emergency order is clearly in opposition to the will of Congress," Paul wrote in the op-ed on Sunday. Paul's op-ed comes after he told Republicans in Kentucky at a dinner on Saturday night that he could not "vote to give the president the power to spend money that hasn’t been appropriated by Congress." "Every single Republican I know decried President Obama’s use of executive power to legislate. We were right then. But the only way to be an honest officeholder is to stand up for the same principles no matter who is in power," Paul writes in the op-ed.
But Paul appears to go a step further in the Sunday op-ed, specifically saying he will support the resolution of disapproval when it comes on the Senate floor in a matter of days and outlining his reasons for supporting it.
"I stand with the president often, and I do so with a loud voice. Today, I think he’s wrong, not on policy, but in seeking to expand the powers of the presidency beyond their constitutional limits," Paul wrote.
Paul's vote gives supporters of the resolution blocking the emergency declaration their crucial 51st vote needed to send the measure to Trump's desk, where he's warned that he will veto it.
With all 47 senators in the Democratic caucus expected to support the resolution of disapproval, they needed to flip four Republicans. In addition to Paul, Sens. Susan Collins
Susan Margaret CollinsThe Hill's Morning Report — Mueller aftermath: What will House Dems do now? Collins backs having Mueller testify Graham says he's 'not interested' in Mueller testifying MORE (R-Maine), Lisa Murkowski
Lisa Ann MurkowskiCain says he 'won't run away from criticism' in push for Fed seat Cain says he won't back down, wants to be nominated to Fed License to discriminate: Religious exemption laws are trampling rights in rural America MORE (R-Alaska) and Thom Tillis
Thomas (Thom) Roland TillisPro-life Christians are demanding pollution protections Embattled senators fill coffers ahead of 2020 Abrams: Schumer has been 'relentless but thoughtful' about Senate bid MORE (R-N.C.) are expected to vote for the resolution.
Susan Margaret CollinsThe Hill's Morning Report — Mueller aftermath: What will House Dems do now? Collins backs having Mueller testify Graham says he's 'not interested' in Mueller testifying MORE (R-Maine), Lisa MurkowskiLisa Ann MurkowskiCain says he 'won't run away from criticism' in push for Fed seat Cain says he won't back down, wants to be nominated to Fed License to discriminate: Religious exemption laws are trampling rights in rural America MORE (R-Alaska) and Thom TillisThomas (Thom) Roland TillisPro-life Christians are demanding pollution protections Embattled senators fill coffers ahead of 2020 Abrams: Schumer has been 'relentless but thoughtful' about Senate bid MORE (R-N.C.) are expected to vote for the resolution. 
