Ukrainian president Volodymyr Zelensky appeals to US senators for support ahead of funding showdown with Russia. White House warns that aid will run out by the end of the year. Zelenskyy's address highlights the importance of defending democracy and preventing Putin from winning the war. Zelenskyy's chief of staff, defense minister, and speaker of Ukraine's parliament engage in a lobbying effort in Washington. Senate Republicans condition their support for funding on immigration reforms, which Democrats have rejected.