Perhaps you've heard that Republicans "prefer" smaller government. That's bunk. Smaller government is the law! The U.S. Constitution prohibits the federal government from exercising any powers not expressly granted to it. Most Americans don't know this because the left-leaning national media, which function as the propaganda arm of the Democrats, never let it be known. Opponents of expanded federal powers, rather than being praised as principled statesmen who are being faithful to their oath of office to support the Constitution, are more typically scorned as mean-spirited, narrow-minded, hateful, miserly or worse. But I'm getting ahead of myself. Let's start with the basics.
The powers of Congress are set forth mainly in Section 8 of Article I of the Constitution. The "other Powers" mentioned at the end of the section deal mainly with interactions with the Executive and Judicial branches (legislation, veto overrides, confirmations, impeachments, etc.) and such things as treaty ratifications and amending the Constitution. What's really instructive is what's not in Section 8: agriculture, housing, education, health, welfare, national retirement plans and many other things that the federal government routinely involves itself in today. Expenditures for these things constitute the great majority of federal spending and are violations of the rule of law. Every vote for these things is a violation of the legislator's oath of office to support the Constitution. Nearly all originated with the Democrats.
The list of powers is a minimal list of things necessary to unite a collection of previously independent states into a cohesive nation. At the time of the ratification debates, many expressed concern that there was no check on expansion of federal powers beyond this list. Therefore, the Tenth Amendment, the last article of the Bill of Rights, was passed, reading: "The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people." The Tenth Amendment is still theoretically in force but is generally simply ignored.
Don't take my word for any of this, READ IT! It's YOUR Constitution, the plan for YOUR government of YOUR country. If you have no idea how it's intended to work you've really got no business choosing the people responsible for making it work and shouldn't be voting, especially for people who have no idea themselves or, worse yet, don't care.
The Democrats vocally defend those parts of the Constitution that suit their purposes, but run roughshod over those that don't. They treat their oath of office as a joke (assuming they've even read the Constitution). Much of federal spending has become little more than the largest source of campaign funding in that it buys the votes of particular constituencies (with your money and mine) for those members of Congress who will support the continuation or expansion of those constituencies' pet programs, regardless of constitutionality. Even many Republicans have been swept along by the gravy train, finding it too difficult to run against Santa Claus when the media will only paint them as villains for principled opposition.
Do these unconstitutional federal expenditures accomplish any good? Sure, and many are very popular. But that's not the test of their validity. If they are unlawful they should not exist. It wouldn't be difficult for any of us to do lots of good for others given unlimited access to other people's money. But funding good works by forcibly confiscating our neighbors' money through the unlawful exercise of the power of government is not commendable charity. It is theft.