  We apply a generalized field ansatz to describe the spherically symmetric
sector of classical solutions of the electroweak theory. This sector contains
Abelian magnetic monopoles labeled by their magnetic charge $n=\pm 1,\pm
2,\ldots$, the non-Abelian monopole for $n=\pm 2$ found previously by Cho and
Maison (CM), and also the electric oscillating solutions. All magnetic
monopoles have infinite energy. We analyze their perturbative stability and use
the method of complex spacetime tetrad to separate variables and reduce the
perturbation equations to multi-channel Schroedinger-type eigenvalue problems.
The spectra of perturbations around the CM monopole do not contain negative
modes hence this solution is stable. The $n=\pm 1$ Abelian monopole is also
stable, but all monopoles with $|n|\geq 2$ are unstable with respect to
perturbations with angular momentum $j=|n|/2-1$. The Abelian $|n|=2$ monopole
is unstable only within the $j=0$ sector whereas the CM monopole also has
$|n|=2$ and belongs to the same sector, hence it may be viewed as a stable
remnant of the decay of the Abelian monopole. One may similarly conjecture that
stable remnants exist also for monopoles with $|n|>2$, hence the CM monopole
may be just the first member of a sequence of non-Abelian monopoles with higher
magnetic charges. Only the CM monopole is spherically symmetric while all
non-Abelian monopoles with $|n|>2$ are not rotationally invariant.
