Live updates: Trump's presidential transition, 2024 election news

Republicans on Capitol Hill are laying the groundwork for pushing through an ambitious agenda with President-elect Donald Trump when they have complete control of Washington next January – a rare Republican trifecta that party leaders believe is now in comes within reach.

And this time they will be ready to use it.

Their goal is to quickly begin crafting large parts of the Trump administration's agenda, starting with a major economic package focused on taxes, energy policy, border security and deregulation, according to two people familiar with the discussions.

Republican leaders are dreaming of another big tax package as many tax provisions are set to expire at the end of 2025.

Also on the table: It may roll back parts of President Joe Biden's signature Inflation Reduction Act, a sweeping economic and climate bill that Democrats passed when they unified government at the start of Biden's term, a source familiar with the discussions told CNN.

Republicans also see an opportunity for other major issues such as House Republicans' tough immigration proposals, which have been stalled since the chamber passed them last year as Senate Democrats and the Biden White House strongly rejected the plan .

Remember: With Republicans gaining a majority in the Senate, implementation of Trump's agenda will depend on Republicans retaining a majority in the House of Representatives. CNN has not yet made a prediction in the fight for control of the House of Representatives. But key gains in Pennsylvania and Michigan are giving party leaders hope that a breakthrough is in sight, and senior Republicans are confident they will retain their slim majority.

Even with unified GOP control, Republicans would face challenges. One problem is the political calculation: Republicans in the House of Representatives believe that it won't be much if they retain the majority. Mike Johnson – who is expected to retain his position as speaker – would have just a few votes left. And their current slim majority is plagued by divisions and obstacles.

Read more about the Republican agenda.

CNN's Danya Gainor contributed to this report.